Package netlib.specfun

Class MachineConst

java.lang.Object
netlib.specfun.MachineConst
public class MachineConst
extends java.lang.Object
Common machine-dependent constants used in Caly0 and Caly1. (Using recommended values for "IBM PC (8087) (D.P.)", see comments below.) 
// C*******************************************************************
// C
// C Explanation of machine-dependent constants
// C
// C   XINF   = largest positive machine number
// C   XMAX   = largest acceptable argument.  The functions AINT, SIN
// C            and COS must perform properly for  ABS(X) .LE. XMAX.
// C            We recommend that XMAX be a small integer multiple of
// C            sqrt(1/eps), where eps is the smallest positive number
// C            such that  1+eps > 1.
// C   XSMALL = positive argument such that  1.0-(X/2)**2 = 1.0
// C            to machine precision for all  ABS(X) .LE. XSMALL.
// C            We recommend that  XSMALL < sqrt(eps)/beta, where beta
// C            is the floating-point radix (usually 2 or 16).
// C
// C     Approximate values for some important machines are
// C
// C                          eps      XMAX     XSMALL      XINF
// C
// C  CDC 7600      (S.P.)  7.11E-15  1.34E+08  2.98E-08  1.26E+322
// C  CRAY-1        (S.P.)  7.11E-15  1.34E+08  2.98E-08  5.45E+2465
// C  IBM PC (8087) (S.P.)  5.96E-08  8.19E+03  1.22E-04  3.40E+38
// C  IBM PC (8087) (D.P.)  1.11D-16  2.68D+08  3.72D-09  1.79D+308
// C  IBM 195       (D.P.)  2.22D-16  6.87D+09  9.09D-13  7.23D+75
// C  UNIVAC 1108   (D.P.)  1.73D-18  4.30D+09  2.33D-10  8.98D+307
// C  VAX 11/780    (D.P.)  1.39D-17  1.07D+09  9.31D-10  1.70D+38
// C
// C*******************************************************************
Anmerkung: Intern wird auf D1mach zurückgegriffen.
Author:
reiser

  • Field Summary

    Fields 
    Modifier and Type Field Description
    static double XINF
    largest positive machine number ( = d1mach(2) ).
    static double XMAX
    =4*sqrt(1/eps) for IBM-PC (with eps = d1mach(4)).
    static double XSMALL
    =sqrt(eps)/4 for IBM-PC (with eps = d1mach(4)).

  • Method Summary

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • XINF

      public static final double XINF
      largest positive machine number ( = d1mach(2) ).

    • XSMALL

      public static final double XSMALL
      =sqrt(eps)/4 for IBM-PC (with eps = d1mach(4)).

    • XMAX

      public static final double XMAX
      =4*sqrt(1/eps) for IBM-PC (with eps = d1mach(4)).